Circuit boards and the IC substrates produced for the optoelectronics and semiconductor industries are trending toward high-speed, high density, intensive, and high integration because of the rise in popularity of the “Cloud”, the “Internet”, the “Internet of things” concept, enhancement of 4G and 5G communication technologies, and improvement in display technologies. The required properties of circuit boards and the IC substrates of the future are not only low dielectric constant and high insulation, but also low dielectric loss and high thermal conductivity.
For example, the simple structure of the copper clad laminate in a circuit board from top to bottom is copper foil, dielectric layer, and copper foil, respectively. However, the middle dielectric layer is usually composed of a resin, glass fiber cloth, or insulation paper with low thermal conductivity, resulting in poor thermal conductivity of the copper clad laminate. In general, a large amount of thermally conductive powder is often added to the dielectric layer to increase the thermal conductivity of the dielectric layer. However, the resin between the thermally conductive powder is not thermally conductive, such that the thermally conductive effect of the thermally conductive powder dispersed in the resin is limited.
A novel thermally conductive resin is called for to overcome the above issue and to increase the thermal conductivity of the dielectric layer between the copper foils.